The 1920s were perhaps the first really big boom time in terms of consumerism. There were, for the first time, a huge number of consumer goods. People had the money to buy them and there were ways (buying on credit, Sears catalog) to buy. This led to a big boom in consumption.

The 1950s were the start of the change in race relations that would really take off in the 1960s. It was during the 1950s that the Brown v. Board of Education case was decided. It was also in this decade that the Montgomery Bus Boycott happened.

In both the 1920s and 1950s, we had a real, sizable middle class, with money to spend and some time on their hands, so the decades share a materialist feeling in society and the money with which to buy new consumer goods.

Race relations aren't quite as similar between those two time periods, in that during the 1920s, Jim Crow segregation laws were still typical in many states, and while the Harlem Renaissance advanced black culture, very few whites in the country recognized it as a social achievement. If anything, the 1920s were more racist than decades past, but more about immigrants than about only African-Americans.

The 1950s represented a decade of racial struggle for civil rights, with support from the Supreme Court in 1954's Brown vs. Board of Education and for the first time, support from a significant number of whites.